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Diverse bee communities pollinate fruits and vegetables, and the composition of these communities has been described for many specialty crops in major production regions. However, pollinator communities in landscapes dominated by agronomic crops may differ in species composition and the contribution of wild bees. With over 4 million ha of maize and soybean, Indiana presents a novel landscape to compare pollinator communities among specialty crops that differ in their use of managed bees and bloom phenology, with potential implications for the composition of wild bee communities and their contributions to flower visitation. We sampled pollinator communities with flower observations and pan traps in spring-blooming apples and blueberries and summer-blooming tomatoes and watermelons, allowing us to compare communities between specialty crops with overlapping and distinct bloom times. Apples, blueberries, and watermelons were stocked with honey bees, and watermelons additionally had managed bumble bees. Across two years of sampling, we observed 1,651 flower visits by 13 taxa, collected 1,967 bees, and identified 84 taxa from collected specimens. Apples and blueberries hosted the richest pollinator communities (34 and 51 taxa, respectively) followed by watermelons (22 taxa), and tomatoes (19 taxa). While 70% of flower visits in apples and blueberries were attributed to honey bees, wild bees accounted for 82% and 99% of flower visits in watermelons and tomatoes, respectively. Our results indicate that distinct pollinator communities persist among co-flowering specialty crops in a landscape dominated by maize and soybean production and underscore the contribution of wild bees for specialty crop pollination, particularly in watermelons and tomatoes.

Abstract Introduction Tomatoes are among the most popular horticultural crops cultivated in high tunnels. Due to space limitations in these enclosed environments, some tomatoes are produced in succession (i.e., without rotation) across years, which could lead to yield reductions over time. However, the impact of tomato monocultures on productivity in high tunnels and strategies to buffer against yield declines need further testing. Materials and Methods We used a 4‐year field experiment whereby heirloom tomatoes (cv. Cherokee Purple and Black Krim) were grown in the same high tunnel soil over time. We tested the impact of both tomato grafting and companion planting on aboveground vegetative biomass and fruit yield. For the grafting treatment, we used the commercially available Maxifort and wild tomato, Solanum pimpinellifolium, as rootstocks. For companion planting, we seeded open alleys with clover and spatially shifted crop beds each year such that tomatoes were transplanted into the previous year's clover planting. Results Our data indicate that the companion (clover) treatment had little to no impact on tomato production, while grafting to Maxifort rootstock had a significant positive effect on biomass and yield. However, beneficial effects of grafting were only observed over time, in years three (+71% inc. in biomass) and four (+77% inc. in biomass, +38% inc. in yield) of the experiment; not during the initial 2 years. Leaf (SPAD) and fruit (Brix) metrics were unaffected by any of the treatments. Conclusion Overall, our results suggest that grafting tomatoes with commercially available rootstock is an effective tool for maintaining production in high tunnel monocultures over time.

Abstract Impacts of insecticide use on the health of wild and managed pollinators have been difficult to accurately quantify in the field. Existing designs tend to focus on single crops, even though highly mobile bees routinely forage across crop boundaries. We created fields of pollinator-dependent watermelon surrounded by corn, regionally important crops in the Midwestern US. These fields were paired at multiple sites in 2017–2020 with the only difference being pest management regimes: a standard set of conventional management (CM) practices vs. an integrated pest management (IPM) system that uses scouting and pest thresholds to determine if/when insecticides are used. Between these two systems we compared the performance (e.g., growth, survival) of managed pollinators—honey bees (Apis mellifera), bumble bees (Bombus impatiens)—along with the abundance and diversity of wild pollinators. Compared to CM fields, IPM led to higher growth and lower mortality of managed bees, while also increasing the abundance (+ 147%) and richness (+ 128%) of wild pollinator species, and lower concentrations of neonicotinoids in the hive material of both managed bees. By replicating realistic changes to pest management, this experiment provides one of the first demonstrations whereby tangible improvements to pollinator health and crop visitation result from IPM implementation in agriculture.

Weed seed biocontrol by omnivorous mice and insects can limit weed seedbanks, but this ecosystem service can be difficult to predict given the broad diet breadth of seed predators and their potential for intraguild predation. Seed foraging behavior is further modified by fluctuating cues of predation risk from higher trophic levels and the availability of refuge habitat. Uncertainty about whether co-occurring insects and mice additively contribute to weed biocontrol or interfere with each other via intraguild predation limits our ability to recommend habitat management strategies that reliably promote seed destruction. Using seed removal assays, fluorescent powder tracking, and stable isotope analyses, we assessed effects of a predation risk cue (moonlight) on mouse foraging patterns in a patchwork of vegetated and exposed plots in a cultivated field. Mouse foraging activity decreased on exposed ground during the full moon, compared to dark nights, yet foraging movements were unaffected by moon cycle within refuge patches. Weed seed consumption was more than three times higher in cover than exposed soil, and 78% of that difference was attributable to invertebrate granivores. Mice and invertebrate granivores both exhibited higher foraging activity in cover, indicating co-occurrence of intraguild predators and prey. However, stable isotope analyses of fecal samples revealed that mice captured in refuge habitats fed at slightly lower trophic levels than those in exposed habitats (suggesting minimal intraguild predation in refuge habitat), and mouse diet was unaffected by moonlight. Despite increased availability of invertebrate prey in cover patches, mice do not appear to preferentially exploit prey when avoiding their own predators or interfere with weed seed predation. Therefore, functional redundancy of mice and invertebrate seed predators in cover crops and other refuge habitats may strengthen and stabilize weed seed biocontrol.

Objectives: Elderly are an understudied, high-risk group vulnerable to severe COVID-19. We comprehensively analyzed the durability of humoral and cellular immune responses after BNT162b2 vaccination and SARS-CoV-2 infection in elderly and younger adults. Methods: Home-dwelling old (n = 100, median 86 years) and younger adults (n = 449, median 38 years) were vaccinated with two doses of BNT162b2 vaccine at 3-week intervals and followed for 9-months. Vaccine-induced responses were compared to home-isolated COVID-19 patients (n = 183, median 47 years). Our analysis included neutralizing antibodies, spike-specific IgG, memory B-cells, IFN-γ and IL-2 secreting T-cells and sequencing of the T-cell receptor (TCR) repertoire. Results: Spike-specific breadth and depth of the CD4+ and CD8+ TCR repertoires were significantly lower in the elderly after one and two vaccinations. Both vaccinations boosted IFN-γ and IL-2 secreting spike-specific T-cells responses, with 96 % of the elderly and 100 % of the younger adults responding after the second dose, although responses were not maintained at 9-months. In contrast, T-cell responses persisted up to 12-months in infected patients. Spike-specific memory B-cells were induced after the first dose in 87 % of the younger adults compared to 38 % of the elderly, which increased to 83 % after the second dose. Memory B-cells were maintained at 9-months post-vaccination in both vaccination groups. Neutralizing antibody titers were estimated to last for 1-year in younger adults but only 6-months in the older vaccinees. Interestingly, infected older patients (n = 15, median 75 years) had more durable neutralizing titers estimated to last 14-months, 8-months longer than the older vaccinees. Conclusions: Vaccine-induced spike-specific IgG and neutralizing antibodies were consistently lower in the older than younger vaccinees. Overall, our data provide valuable insights into the kinetics of the humoral and cellular immune response in the elderly after SARS-CoV-2 vaccination or infection, highlighting the need for two doses, which can guide future vaccine design.Clinical trials.gov; NCT04706390.

Life skills, also known as psychosocial and non-cognitive skills, are critical to children’s development and well-being as they progress through early life courses but difficult to measure. The present study aims at validating a culturally adapted version of the Multidimensional Scale of Life Skills in Late Childhood in the context of primary school of rural Afghanistan and Pakistan. The instrument was face validated by six of the authors. The scale was found accessible to students’ grades three to five despite its original target of late childhood. Content validation was also carried out by the authors to evaluate the representativeness of the scale items for the various dimensions of life skills. The items were found relevant for the seven dimensions of life skills considered. The scale also showed overall good internal consistency, acceptable test retest and inter rate consistence and high responsiveness. Exploratory factorial analysis showed that 4 and 3 factors explained 40% and 37% of the total variance respectively in Pakistan and Afghanistan.

Edible insects have gained attention due to their impressive nutritional composition, as well as their efficient use of natural resources. However, a research gap remains on the applications of insect chitosan, especially as it relates to their potential use as food packaging material. Chitosan from two reared cricket species (Acheta domesticus and Gryllodes sigillatus) was evaluated for use as food packaging material. Cricket chitosan films (CCF) were structurally similar to commercial shrimp chitosan films (SCF) at controlled glycerol levels, as seen by shared spectral peaks in FT-IR analyses. Mechanical properties of CCF showed they had equal or greater tensile strength when compared to commercial SCF, although flexibility was lower. Scanning electron microscopy showed increased roughness of microstructure, likely increasing the tortuosity. As a result, CCF had improved water vapor permeability compared to commercial SCF. Melanin complexes present in cricket chitin and chitosan increased hydrophobicity and decreased light transmittance. This study also revealed that intrinsic species differences, which occur during insect and crustacean exoskeleton development, could have effects on the functionality of chitosan packaging materials. Overall, CCF were found to be as effective as commercial SCF, while providing additional advantages. CCF derived from reared crickets have good mechanical and barrier properties, and improved water resistance and light barrier characteristics. Edible cricket chitosan has the potential to be used as bio-based packaging material for food and pharmaceutical applications.

Root-associated microbial communities are well known for their ability to prime and augment plant defenses that reduce herbivore survival or alter behavior (i.e., resistance). In contrast, the role root microbes play in plant tolerance to herbivory, an evolutionarily sustainable alternative to resistance, is overlooked. In this study, we aimed to expand our limited understanding of what role rhizosphere microbial communities play in supporting tolerance to insect damage. Using domesticated tomatoes and their wild ancestors (Solanum spp.), we first documented how tobacco hornworm (Manduca sexta) herbivory impacted tomato fruit production in order to quantify plant tolerance. We then characterized the bacterial and fungal rhizosphere communities harbored by high and low tolerance plants. Wild tomatoes excelled at tolerating hornworm herbivory, experiencing no significant yield loss despite 50% leaf area removal. Their domesticated counterparts, on the other hand, suffered 26% yield losses under hornworm herbivory, indicating low tolerance. Ontogeny (i.e., mid- vs. late-season sampling) explained the most variation in rhizosphere community structure, with tomato line, tolerance, and domestication status also shaping rhizosphere communities. Fungal and bacterial community traits that associated with the high tolerance line include (1) high species richness, (2) relatively stable community composition under herbivory, and (3) the relative abundance of taxa belonging to Stenotrophomonas, Sphingobacterium, and Sphingomonas. Characterizing tolerance-associating microbiomes may open new avenues through which plant defenses are amended in pest management, such as plant breeding efforts that enhance crop recruitment of beneficial microbiomes.

Abstract Agriculture has long employed phylogenetic rules whereby farmers are encouraged to rotate taxonomically unrelated plants in shared soil. Although this forms a central tenet of sustainable agriculture, strangely, this on‐farm “rule of thumb” has never been rigorously tested in a scientific framework. To experimentally evaluate the relationship between phylogenetic distance and crop performance, we used a plant–soil feedback approach whereby 35 crops and weeds varying in their relatedness to tomato (Solanum lycopersicum) were tested in a two‐year field experiment. We used community profiling of the bacteria and fungi to determine the extent to which soil microbes contribute to phenotypic differences in crop growth. Overall, tomato yield was ca. 15% lower in soil previously cultivated with tomato; yet, past the species level there was no effect of phylogenetic distance on crop performance. Soil microbial communities, on the other hand, were compositionally more similar between close plant relatives. Random forest regression predicted log10 phylogenetic distance to tomato with moderate accuracy (R2 = .52), primarily driven by bacteria in the genus Sphingobium. These data indicate that, beyond avoiding conspecifics, evolutionary history contributes little to understanding plant–soil feedbacks in agricultural fields; however, microbial legacies can be predicted by species identity and relatedness.

Abstract Background Afghanistan has one of the world’s highest maternal mortality ratios, with more than 60% of women having no access to a skilled birth attendant in some areas. The main challenges for childbearing Afghan women are access to skilled birth attendance, emergency obstetric care and reliable contraception. The NGO-based project Advancing Maternal and Newborn Health in Afghanistan has supported education of midwives since 2002, in accordance with the national plan for midwifery education. The aim of this study is to explore women’s experiences of professional midwifery care in four villages in Afghanistan covered by the project, so as to reveal challenges and improve services in rural and conflict-affected areas of the country. Methods An exploratory case-study approach was adopted. Fourteen in-depth interviews and four focus-group discussions were conducted. A total of 39 women participated – 25 who had given birth during the last six months, 11 mothers-in-law and three community midwives in the provinces of Kunar and Laghman. Data generated by the interviews and observations was analysed using thematic content analysis. Findings Many of the women greatly valued the trained midwives’ life-saving experience, skills and care, and the latter were important reasons for choosing to give birth in a clinic. Women further appreciated midwives’ promotion of immediate skin-to-skin contact and breastfeeding. However, some women experienced rudeness, discrimination and negligence on the part of the midwives. Moreover, relatives’ disapproval, shame and problems with transport and security were important obstacles to women giving birth in the clinics. Conclusions Local recruitment and professional education of midwives as promoted by Afghan authorities and applied in the project seem successful in promoting utilisation and satisfaction with maternal and neonatal health services in rural Afghanistan. Nevertheless, the quality of the services is still lacking, with some women complaining of disrespectful care. There seems to be a need to focus more on communication issues during the education of midwives. An increased focus on in-service training and factors promoting quality care and respectful communication is necessary and should be prioritised.

While research suggests that pollinator decline is linked with agricultural practices, it is unclear whether farmers share this view and adapt management to promote pollinators based on their understanding of these threats. To address these issues, we surveyed farmers of pollinator-dependent cucurbit crops across four states in the Midwest, USA. We grouped farmers by their perceptions of pollinator declines and routes of pesticide exposure and used statistical models to evaluate if farmers manage pests and pollinators based on these perceptions. Out of 93 completed surveys, 39% of farmers believed pollinators were in decline. When grouped, 17% of farmers were classified as proponents, ranking (on a 1–5 Likert scale) the factors mediating pesticide exposure and pollinator declines as important or highly important. For comparison, 44 and 39% of farmers were classified as neutral or skeptical, respectively, of these same factors. Compared to the neutral and skeptic groups, proponents were on average younger, had fewer years farming but more years in family farming, and were more dependent on income from outside the farming system. Proponents also on average reported smaller farms, higher pest richness, more land in cucurbit production, and greater richness of crops that are not pollinator dependent, when compared to the neutrals and skeptics. We did not find pest and pollinator management to be related to farmer perceptions of pollinator decline or routes of pesticide exposure, but farmers classified as pollinator “proponents” were more likely to indicate participation in future pollinator habitat restoration programs. Rather, management strategies were better explained by on-farm environmental conditions (e.g., pest richness, farm size, number of pollinator dependent crops) and economic factors (e.g., sources of income). Generally, our research shows that farmers who perceive pollinator threats may not be using pollinator supportive practices. Thus, while some farmers believe in pollinator declines, there remains a need to connect this knowledge with on-farm practices.

Abstract Small, mobile insects are notoriously challenging to track across landscapes and manage in agricultural fields. However, genetic differentiation among insect populations and host plants acquired through host‐associated differentiation could be exploited to infer movement within crop systems and damage potential. Although many insects exhibit host‐associated differentiation, management strategies for insect vectors of plant pathogens assume a homogenous population. Nevertheless, phenotypic changes derived from host‐associated differentiation could manifest in altered behavior or physiology affecting the likelihood of vector–pathogen–plant interactions, or the subsequent efficiency of pathogen transmission. We used SNPs to assess genotypic structure and host‐associated differentiation in the cowpea aphid, Aphis craccivora Koch (Hemiptera: Aphididae). To do so, we sampled A. craccivora across the Midwestern United States. from two host plants, alfalfa (Medicago sativa) and black locust (Robinia pseudoacacia)—putative source populations for winged migrants. Simultaneously, we sampled winged A. craccivora landing in pumpkin fields where they transmit viruses. Structure analyses supported host‐associated differentiation by identifying two major genotypic groups: an alfalfa group containing a single multilocus genotype and a locust group containing all others. Winged locust‐group aphids landed at a much greater magnitude within focal fields during year 2 than year 1, while those in the alfalfa group remained fairly consistent. Spatial autocorrelation analyses indicated locust‐group aphid movement was characterized by small‐scale dispersal during year 2, likely originating from populations within 10 km. We also detected strong temporal differences in colonization from the two host plants. Early in the summer, most winged aphids (79.4%) derived from the locust group, whereas late in the summer more (58.3%) were from the alfalfa group. Because early crop growth stages are more susceptible to damage from aphid‐vectored viruses, these data implicate locust as the more important source and illustrate how host‐associated differentiation can be used to track dispersal and inform management of heterogeneous pest populations.

Aboveground herbivory can impact the root-associated microbiome, while simultaneously different soil microbial communities influence herbivore performance. It is currently unclear how these reciprocal top-down and bottom-up interactions between plants, insects and microbes vary across different soils and over successive plant generations. In this study, we examined top-down impacts of above-ground herbivory on the rhizosphere microbiome across different soils, assessed bottom-up impacts of soil microbial community variation on herbivore performance, and evaluated their respective contributions to soil legacy effects on herbivore performance. We used Macrosiphum euphorbiae (potato aphid) and Solanum pimpinellifolium (wild tomato) to capture pre-domestication microbiome interactions with a specialist pest. First, using 16S rRNA sequencing we compared bacterial communities associated with rhizospheres of aphid-infested and uninfested control plants grown in three different soils over three time points. High aphid infestation impacted rhizosphere bacterial diversity in a soil-dependent manner, ranging from a 22% decrease to a 21% increase relative to uninfested plants and explained 6–7% of community composition differences in two of three soils. We next investigated bottom-up and soil legacy effects of aphid herbivory by growing wild tomatoes in each of the three soils and a sterilized “no microbiome” soil, infesting with aphids (phase one), then planting a second generation (phase two) of plants in the soil conditioned with aphid-infested or uninfested control plants. In the first phase, aphid performance varied across plants grown in different soil sources, ranging from a 20 to 50% increase in aphid performance compared to the “no microbiome” control soil, demonstrating a bottom-up role for soil microbial community. In the second phase, initial soil community, but not previous aphid infestation, impacted aphid performance on plants. Thus, while herbivory altered the rhizosphere microbiome in a soil community-dependent manner, the bottom-up interaction between the microbial community and the plant, not top-down effects of prior herbivore infestation, affected herbivore performance in the following plant generation. These findings suggest that the bottom-up effects of the soil microbial community play an overriding role in herbivore performance in both current and future plant generations and thus are an important target for sustainable control of herbivory in agroecosystems.

Monarch butterflies are undergoing a long-term population decline, which has led to a search for potential causes underlying this pattern. One poorly studied factor is exposure to non-target pesticides on their primary host-plant, the common milkweed Asclepias syriaca, during larval development. This species frequently grows near agricultural fields in the Midwestern U.S., but the spectrum of pesticides encountered by monarch caterpillars on milkweed leaves is unknown. Further, it is unclear whether pesticide exposure can be avoided by isolating restored milkweed patches at sites far from cropland. Over 2 years, we analyzed 1,543 milkweed leaves across seven sites in northwestern Indiana for the presence and concentration of a range of commonly used agricultural insecticides, fungicides, and herbicides. Additionally, we tested the ability of local (i.e., nearest linear distance to crop field) and landscape-level (i.e., % of corn/soybean in 1 km radius) variables to predict the presence of pesticides on focal milkweeds. Overall, we detected 14 pesticides−4 insecticides, 4 herbicides, 6 fungicides—on milkweeds that varied widely in their prevalence and concentration. The neonicotinoid clothianidin, the only pesticide for which toxicity data are available in monarchs, was detected in 15–25% of plants in June with nearly 60% of milkweeds at some sites testing positive (mean conc. = 0.71 and 0.48 ng/g in 2015 and 2016, respectively); however, no samples from July or August contained clothianidin. The related neonicotinoid thiamethoxam and the pyrethroid deltamethrin were detected in most (>75%) samples throughout the season, but only in the second year of the study. For thiamethoxam, isolating milkweeds 50–100 m from the nearest corn or soybean field tended to decrease the concentration and likelihood of detecting residues, whereas landscape composition surrounding milkweed sites had comparatively weak predictive power. These data suggest that monarch caterpillars frequently consume a diversity of pesticides in their diet; the lethal or sublethal impacts of this exposure remain to be tested.

Western honey bees (Apis mellifera) are dominant crop pollinators, and access to summer forage is a critical factor influencing colony health in agricultural landscapes. In many temperate agricultural regions, honey bees forage extensively from non-native plants during the summer, but it is unclear whether the use of these species is due to honey bee preference for these plants or is a result of their relative abundance. The foraging choices made by native bees that have evolved with native plants can reveal the seasonal availability of native plant pollens, and so we quantified the pollen collected by 181 wild bee species native to Michigan. Pollen was also trapped from honey bee colonies during the summer to confirm the peak period of non-native pollen collection in this region. Across the state, the generic richness of native pollens collected by wild bees peaked in May before linearly declining into September. Wild social and solitary bees collected a similar proportion of their pollen from non-native plants from April to July, but during August and September social bees collected a significantly greater proportion from non-natives. At a local scale, honey bees collected the majority of their pollen from non-native plants between 4 July and 21 August, with the same trend seen in both social and solitary bees. Across the region, a significantly greater proportion of the solitary bee species that peak during this time are specialists, most of which collect from native plant species that are little utilized by social bees for pollen, such as Dasiphora, Helianthus, Physalis, and Vernonia. Our results suggest that Michigan has relatively few native flowering resources during the height of the summer, and that many of those which flower during this time are used primarily by specialized solitary bee species rather than the social bee community, including honey bees. As a result, non-native plant species with a late summer flowering phenology fill a forage gap and thus can contribute to the diet of both honey bees and generalist wild bees during this time, despite the well-documented negative impacts of these species on native plant communities.

Rheumatoid arthritis (RA) patients have nearly twice the risk of cardiovascular disease (CVD) compared to the general population. We aimed to assess, in a predominantly Black population, the prevalence of traditional and RA-specific CVD risk factors and therapeutic patterns. Utilizing ICD codes, we identified 503 RA patients ≥18 years old who were seen from 2010 to 2017. Of them, 88.5% were Black, 87.9% were women and 29.4% were smokers. CVD risk factors (obesity, diabetes, hypertension, dyslipidemia) were higher than in previously reported White RA cohorts. Eighty-seven percent of the patients had at least one traditional CVD risk factor, 37% had three or more traditional CVD risk factors and 58% had RA-specific risk factors (seropositive RA, >10 years of disease, joint erosions, elevated inflammatory markers, extra-articular disease, body mass index (BMI) < 20). CV outcomes (coronary artery disease/myocardial infarction, heart failure, atrial fibrillation and stroke) were comparable to published reports. Higher steroid use, which increases CVD risk, and lesser utilization of biologics (decrease CV risk) were also observed. Our Black RA cohort had higher rates of traditional CVD risk factors, in addition to chronic inflammation from aggressive RA, which places our patients at a higher risk for CVD outcomes, calling for revised risk stratification strategies and effective interventions to address comorbidities in this vulnerable population.

Herbivores are squeezed between the two omnipresent threats of variable food quality and natural enemy attack, but these two factors are not independent of one another. The mechanisms by which organisms navigate the dual challenges of foraging while avoiding predation are poorly understood. We tested the effects of plant defense and predation risk on herbivory in an assemblage of leaf-chewing insects on Solanum lycopersicum (tomato) that included two Solanaceae specialists (Manduca sexta and Leptinotarsa decemlineata) and one generalist (Trichoplusia ni). Defenses were altered using genetic manipulations of the jasmonate phytohormonal cascade, whereas predation risk was assessed by exposing herbivores to cues from the predaceous stink bug, Podisus maculiventris. Predation risk reduced herbivore food intake by an average of 29% relative to predator-free controls. Interestingly, this predator-mediated impact on foraging behavior largely attenuated when quantified in terms of individual growth rate. Only one of the three species experienced lower body weight under predation risk and the magnitude of this effect was small (17% reduction) compared with effects on foraging behavior. Manduca sexta larvae, compensated for their predator-induced reduction in food intake by more effectively converting leaf tissue to body mass. They also had higher whole-body lipid content when exposed to predators, suggesting that individuals convert energy to storage forms to draw upon when risk subsides. In accordance with expectations based on insect diet breadth, plant defenses tended to have a stronger impact on consumption and growth in the generalist than the two specialists. These data both confirm the ecological significance of predators in the foraging behavior of herbivorous prey and demonstrate how sophisticated compensatory mechanisms allow foragers to partially offset the detrimental effects of reduced food intake. The fact that these mechanisms operated across a wide range of plant resistance phenotypes suggests that compensation is not always constrained by reduced food quality.

Several individual miRNAs (miRs) have been implicated as potent regulators of important processes during normal and malignant hematopoiesis. In addition, many miRs have been shown to fine-tune intricate molecular networks, in concert with other regulatory elements. In order to study hematopoietic networks as a whole, we first created a map of global miR expression during early murine hematopoiesis. Next, we determined the copy number per cell for each miR in each of the examined stem and progenitor cell types. As data is emerging indicating that miRs function robustly mainly when they are expressed above a certain threshold (∼100 copies per cell), our database provides a resource for determining which miRs are expressed at a potentially functional level in each cell type. Finally, we combine our miR expression map with matched mRNA expression data and external prediction algorithms, using a Bayesian modeling approach to create a global landscape of predicted miR-mRNA interactions within each of these hematopoietic stem and progenitor cell subsets. This approach implicates several interaction networks comprising a "stemness" signature in the most primitive hematopoietic stem cell (HSC) populations, as well as "myeloid" patterns associated with two branches of myeloid development.

Indirect plant defenses are those facilitating the action of carnivores in ridding plants of their herbivorous consumers, as opposed to directly poisoning or repelling them. Of the numerous and diverse indirect defensive strategies employed by plants, inducible volatile production has garnered the most fascination among plant-insect ecologists. These volatile chemicals are emitted in response to feeding by herbivorous arthropods and serve to guide predators and parasitic wasps to their prey. Implicit in virtually all discussions of plant volatile-carnivore interactions is the premise that plants "call for help" to bodyguards that serve to boost plant fitness by limiting herbivore damage. This, by necessity, assumes a three-trophic level food chain where carnivores benefit plants, a theoretical framework that is conceptually tractable and convenient, but poorly depicts the complexity of food-web dynamics occurring in real communities. Recent work suggests that hyperparasitoids, top consumers acting from the fourth trophic level, exploit the same plant volatile cues used by third trophic level carnivores. Further, hyperparasitoids shift their foraging preferences, specifically cueing in to the odor profile of a plant being damaged by a parasitized herbivore that contains their host compared with damage from an unparasitized herbivore. If this outcome is broadly representative of plant-insect food webs at large, it suggests that damage-induced volatiles may not always be beneficial to plants with major implications for the evolution of anti-herbivore defense and manipulating plant traits to improve biological control in agricultural crops.

Education in Afghanistan and Pakistan is characterised by indicators showing lack of mastering of reading, writing and mathematics literacy skills. To foster effective education systems and provide quality education, experts have encouraged and established various mechanisms of accountability. We conducted participatory workshops with 556 teachers representing 102 primary schools in Afghanistan and Pakistan to investigate their understanding of teachers' roles and responsibilities in education. Teachers acknowledged their own responsibilities for student learning but also emphasized that improving the quality of education should involve providing good teaching and learning environments, child-centred pedagogy, caring relationships, parental involvement, inclusive communities, and respect for teachers.

Abstract  Herbivores induce systemic changes in plant traits, and the strength of these induced responses is often associated with the degree of vascular connectivity that links damaged and undamaged plant tissues. Although this phenomenon is known to occur aboveground in leaves, it is unknown whether or not leaf–root induction similarly follows the vascular architecture of plants. To test for this possibility, we manipulated foliar and root herbivory on tobacco (Nicotiana tabacum) by the leaf-chewing insect Spodoptera exigua and the root-galling nematode Meloidogyne incognita. Subsequent changes in secondary chemistry (alkaloids and phenolics) were measured in leaves and roots that were orthostichous (vertically aligned) and nonorthostichous (opposite) from the herbivore-damaged tissues. Aboveground caterpillar herbivory elicited stronger secondary chemical responses in orthostichous compared with nonorthostichous plant tissues, although the magnitude of this difference was greater in leaves than roots. However, belowground nematode herbivory did not affect the secondary chemistry of tobacco leaves, despite inducing strong local responses in roots. Thus, plant vascular architecture can mediate the magnitude of systemic induction in roots as well as in leaves, with stronger responses in tissues that are more closely aligned. As a result, herbivores that co-occur on the same sector of plant (both aboveground and belowground) may be more likely to affect one another via induced responses than herbivores that occur on plant tissues sharing fewer resources. [ABSTRACT FROM AUTHOR]